Cooling jacket for internalcombustion engines



2,4053%? -CO-MBUSTION ENGINES Aug; E3, 194%.

c. G. PULLIN COOLING JACKET FOR INTERNAL Filed March 23, 1945 FIG Patented Aug. 13, 1946 CQOLING JACKET FOR INTERNAL- COMBUSTION ENGINES Cyril George Pullin, Wimbledon,

London, England, assignor to The Cierva Autogiro Company Limited, London,

England, a British company I Application March 23, 1945, Serial No. 534,273

In Great Britain April 28, 1944 This invention relates to cooling jackets for liquid-cooled internal-combustion engines.

My primar object is to provide a jacket so connected to both a jacketed cylinder head and a cylinder barrel that relative movement between these two parts as a result of differential thermal expansion will be permitted.

A further object of this invention is to provide a very light and simple construction.

In my invention I make the jacket that surrounds the cylinder barrel from a sheet-metal shell which is rubber-bonded directly or indirectly to both the barrel and the cylinder head. The shell, being made of sheet-metal, is very light, and the rubber bonds provide enough resilience to allow for diiferential thermal expansion.

The invention is particularly useful when applied to a jacketed cylinder head that is internally screw-threaded to fit over an externally screw-threaded barrel. In this type of construction the head is heated to enable the barrel to be screwed into it, so that in effect it is shrunk onto the barrel, and the cooling jacket must be fitted after these operations have been carried out.

A construction in accordance with the invention will now be described by way of example with reference to the accompanying drawing in which:

Figure 1 is an axial section through the cylinder head and the end of the barrel of a cylinder equipped with my novel cooling jacket construc- "tion;

Figure 2 shows part of a metal ring and rubber bonding serving for indirect connection of the jacket to the cylinder head shown in Figur 1 and Figure 3 is an enlargement of part of Figure 1 showing the joint at the skirt of the sheet metal coolant jacket.

The construction shown in Figure 1 comprises a cylinder barrel l with an external screw-thread at its upper end which mates with the corresponding thread in a cylinder head 2 provided with an exhaust valve 3 and an inlet valve 4 of standard construction. The head is first heated, then the barrel is screwed in and next a locking ring 2! is tightened up to make the joint between the head and the barrel gas-tight. The head 2 is surrounded by and integral with a cooling jacket 5 so as to leave a, space 6 for circulating water. A water jacket is provided around the end of the barrel in accordance with this invention and takes the form of a sheet-metal shell 2 Claims. (Cl. 123-173) 1 composed of a conical part 8 and a cylindrical part 9 welded to the part 8. The upper end of the part 9 is united to a metal ring it which is bonded by rubber H to an end surface l2 of the cylinder head 2 which lies in a plane at right angles to the axis of the barrel 5. Water ports is are provided in this end surface i2 and the ring H3 is formed with corresponding ports M as shown in Figure 2 so that water can flow from the space within the jacket I to the space 6. In order to prevent the rubber of the bonding ring I! from obscuring the ports l3 and ill when they are brought into registration with one another and the bonding process takes place, liners l 5 are provided around the edges of the registering ports.

When the shell I has been welded or otherwise secured to the ring I [l a cylindrical skirt it integral with the part 8 lies around external cooling fins I! on the barrel i. Rubber bonding material i8 is put in position between these fins ll and the skirt iii and the skirt is then rolled in so that it becomes bonded through the rubber to the fins I] as shown in Figure 3.

A liquid inlet connection is is welded to the 'conical part 8 of the jacket I and a liquid outlet connection 20 is formed in the head 2. Of course if desired the cooling water ma flow in the other 7 direction, that is to say in through the connection 23 and out through the connection l9.

One advantage of the invention is that it provides a simple means of converting an air-cooled cylinder assembly to liquid cooling.

What I claim is:

1. In aliquid-cooled internal combustion engine, a cylinder having a head and a barrel, said head presenting an end surface lying in a plane at right angles to the axis of said barrel, a metal ring rubber-bonded to said surface, and a cooling jacket surrounding said barrel, said jacket comprising a sheet-metal shell rubber-bonded to said barrel and united to said ring.

2. In a liquid-cooled internal combustion engine, a cylinder having a jacketed head and a barrel secured in said head, said head presenting an end surface lying in a plane' at right angles to the axis of said barrel and formed with ports for the passage of cooling liquid into the jacket around said head, a metal ringformed with complementary ports in registration with said firstmentioned pOrts, said metal ring being rubberbonded to said surface, liners around the edges of said registering ports to prevent the bonding rubber from obscuring said ports, and a cooling CYRIL GEORGE PULLIN. 

